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mark; sign
symbol; emblem
badge; crest; flag
evidence; proof
token (of gratitude, affection, etc.)
「標」 has other readings with different meanings.
完了した書類には標を付けておく。
Put a mark on the completed documents.
地図に赤い標を付けて集合場所を示した。
I put a red mark on the map to show the meeting place.
この標があれば道に迷わないだろう。
You probably won't get lost with this marker.